CORVALLIS – Each week in the extended family of college football, one can find connections between players on opposing teams – an old high school teammate here, a relative there – but in the case of Oregon State middle linebacker Kevin “Feti’’ Unga, the ties to BYU run especially deep.

“First of all,’’ said Unga, a junior and the Beavers’ leading tackler. “I’m a member of the Church of Jesus Christ of Latter-day Saints. Just growing up, I’ve always just been a fan (of BYU), being a member of the church.’’

There will be a large Mormon contingent in Corvallis this weekend when the Beavers (1-4) and Cougars (4-2) meet in a rare mid-season, non-conference game. Many of them will be Ungas, cheering on a player who is in the middle of a fast-improving Oregon State defense.

“There’s quite a bit,’’ Unga said, adding up in his head his cousins and second cousins who will come down from the Portland area to watch him play. “Let’s see. There’s probably, twenty? Thirty?’’

Unga, who grew up in Rochester, Calif., has eight siblings, although most of those won’t be attending the 1 p.m. game at Reser Stadium, because of high school activities or football coaching responsibilities.

The Unga family tree includes brother Paul, who played at Arizona State, and cousins Fahu Tahi and Reno Mahe, who were both NFL running backs, as well as uncle Tim Manoa, another former NFL player and member of the 1986 Penn State national championship team.

And there is cousin and current Chicago Bears running back Harvey Unga, who happens to be BYU’s all-time leading rusher. And Devin “Uani’’ Unga, the twin brother of Feti who transferred from Oregon State to BYU after last season and is a walk-on with the Cougars.

“He’s supporting family right now,’’ Feti Unga said of his twin brother, who will pay his own way to Corvallis to watch the game. “He’ll be wearing black and orange.’’

So intertwined are the Ungas and the Beavers and the Cougars that black and orange and blue actually do go together.

It was especially confusing in the 2009 Vegas Bowl, when all the family members – including Feti Unga – were rooting for Harvey’s BYU team.

“It was just a big deal,’’ Feti Unga said, recalling the Beavers’ 44-20 loss to BYU that ended OSU’s five-game bowl winning streak. “Everyone’s rooting for each other. At the time, me and my brother weren’t getting as much (playing time). Every time (Harvey Unga) was out there, I was rooting for him. When he was sitting on the bench, I was rooting for our defense. It’s a family thing.’’

This is the first time the twin Ungas have been apart, except when they went on their missions, and the first time they have played on separate football teams.

“At first it was a little weird for both of us,’’ Feti Unga said. “We grew up together. We both moved to my grandma’s house (in Hawaii, during their high school junior year) together. Now we’re separate.’’

OSU defensive coordinator Mark Banker told Unga this game should be his “Holy War,’’ a reference to the BYU-Utah rivalry, a game won by Utah a month ago, 54-10.

Unga was recruited by OSU and Utah, but only after he told BYU that he was not interested in becoming a Cougar.

“I told BYU ahead of time, just to be honest with them from the beginning, that I kind of didn’t want to go there,’’ Unga said. “I don’t know, I’ve been a fan just being a member of the church. I’m not really a BYU fan, not really the student type to go to BYU.’’

The Beavers are thankful for Unga’s decision. The middle linebacker has had at least seven tackles in each game and had 14 – including three tackles for loss – against UCLA. His 45 tackles (9.0 per game) rank second in the Pac-12, just behind Utah’s Chaz Walker (47).

One of eight defensive starters who have started for the first time in 2011, Unga has been a constant in an OSU defense that has made major strides in the past two weeks.

Against Arizona State and Arizona, the Beavers defense allowed an average of 24 points (the Sun Devils had a special teams score and the Wildcats a defensive touchdown) and 81 rushing yards. Although neither opponent is dominant on the ground, that rushing defense for OSU in October ranks second in the Pac-12 behind Washington and 15th in the nation.

Unga is one of just a handful of Beavers who are missionaries, as opposed to 74 on the BYU roster. He said his two years in Chile are paying off now in maturity, especially given the trying start to OSU’s 2011 season.

“It was a good opportunity to grow, not only spiritually but also mentally,’’ Unga said. “The transition was a bit hard, going from a spiritual life for two years and coming into college life. It was a bit rough. Now that maturity from the mission is starting to kick in, and I’m staying more focused on school and football, it’s helping a lot more – rather than living that so-called college life.’’

A little homesickness is a way of college life, too. But on Saturday, when Unga takes part in his “Holy War,’’ home will come to him.